System for restructuring wrist joints

Abstract

A system for reconstructing joints, particularly wrist joints. The system comprises three main components. A first main component (1) with a front plate (2) to hold an anchoring member screwable into the bone tissue close to the joint, and at least one pin (5) partially hollow, protruding from and the front plate (2) towards the bone tissue. A second main component (14) with a front plate (15) to hold an anchoring member (17) applied in the bone tissue close to the joint, and at least one pin (20) partially hollow, protruding from the front plate (15) towards the bone tissue. A third main component (33) comprising an artificial joint mechanism in the form of an elastomeric material which, by means of pins protruding from the joint mechanism, is intended to be positioned and secured in said hollow pins and/or attachment screws in the front plates (2; 15) of said first and second main components (1; 14) facing each other.

What is claimed: 
     
       1. A system for reconstructing a wrist joint comprising: a first main component comprising a first front plate with an outward facing side for facing toward the hand and an opposite inward facing side, a first anchoring pin supported in the first front plate, protruding from the outward facing side of the front plate and for extending toward a bone on the outward facing side of the first front plate;   a second main component comprising a second front plate having a second inward facing side for facing away from the hand and an opposite second outward facing side, a second anchoring pin supported on the second front plate and for extending into the bone at the second inward facing side of the second plate;   a third main component comprised of elastomeric material and disposed between the inward facing side of the first front plate and the second outward facing side of the second front plate, and means on the first and second plates and on the third component for securing them together, the elastomeric material of the third component being deformable for permitting the hand to move at the wrist, and further comprising guide means disposed on the second component and a control element extending from the guide means for extending into the ulna bone of the wrist, the guide means being connected to the second front plate of the second component, and the guide means being so shaped and positioned as to permit rotary movement of the reconstructed wrist.   
     
     
       2. The system of claim 1, wherein the attachment of the third component to the first and second components comprises pins projecting from the third component into the first and second components. 
     
     
       3. The system of claim 1, wherein the second anchoring pin is intended to extend into the radius bone of the wrist. 
     
     
       4. The system of claim 1 wherein the guide means comprises the second front plate having a guide body with a slot shaped guide opening through it, the control element provided for extending into the ulna bone and securement therein and the control element located outside the guide body and the guide opening thereof, whereby the cooperation of the control element and the guide body enables movement of the hand at the wrist. 
     
     
       5. The system of claim 4 wherein the control element and the slot shaped guide opening are respectively so shaped that the control element is both rotatable and displaceable in both the lateral and vertical directions with respect to the slot shaped guide opening. 
     
     
       6. The system of claim 5 further comprising a sleeve like body of a polymer material inserted in the guide body and the slot shaped guide opening being defined in the sleeve like body. 
     
     
       7. The system of claim 6, wherein the sleeve like body is comprised of a polymer material. 
     
     
       8. The system of claim 7, wherein the first and second main components comprise titanium.